Spark-producing device.



PATENTED DEC. 18, 1906. I. A. TH URSTON. SPARK PRODUCING DEVICE.APPLICATION FILED FEB. 7, 1905.

FREDUS A. THURSTOhL-OF CHICAGO, ILLINOIS. SPARK-PRODUCING DEVICE-Specification of Letters Patent.

Patented Dec. 18, 1906.

lication filed February 11965. Serial No. 244,629.

.To all "wk/ant it may concern:

Be it known that I, FREDUs A. THURSTON,

a citizen of the United States, residing at Chicago, in the county ofCook and State of Illinois, have invented a certain new and usefulImprovement in Spark-Producing Devices, of which the following is afull, clear, concise, and exact description, reference being had to theaccompanying drawings, form ing a part of this specification.

My lnvention relates to spark-plugs for explosive-engines for use inmotor-vehicles,

launches, and the like.

Prominent objects of'the invention are to provide a simple, practical,and inexpensive form of spark-plug; to secure reliabihty andelfectiveness of action,- particularly with the device in a horizontalor inclined position; to

prevent injury of any kind to the operating parts of the device eitherby heat, gas,-'or Water or otherwise to secure a large and. brightflash; to procure very high efficiency of action, and to secureltheforegoing and. otherdesirable results in a simple, practical; andeffective manner.

In the accompanying drawings, Figure 1 is .a longitudinal section of aspark-plug e'm-.

bodying my invention. Fig. 21s an end. view of the device; Fig. 3 is asection taken on line 3 3 in Fig. 1, and Figs. 4 and 5 are views ofdetails of construction.

The spark-p'lpg shown in the drawings for carrying out myinvention,comprises a shell or casing 1, conveniently of cylindrical form and madeopen at both ends. One end'Aispreferablythreaded, as at 2,. to permitthe device to be readily screwed into and out of the cylinder of theengine or other device in which the plug'isto be used. Within the shellor casing 1, which is desirably formed of metal, such as brass or iron,is a spool or bobbin, on which is wound a coil of line wire 3.

' The bob hinis desirably made of mctalas, for

example, of iron or steeland consists of a. central spindle 4 and a pair.of end flanges 5 5?, which are but very little smaller than theinterior of the sh all or casing 1. A layer 6 of insulating material,referably fireproof alsoas, for example, asbestos is arrangerimmediately outside of the spindle 4 of the bobbin, and layers 7 7 ofthe same or. similar material are arranged inside'ofthe flanges 5 5 ofthe bobbin. A layer 8 of the same or similar material is arrangedbetween the coil of wire and theshell 1 and layers 9 and 10 at each endof said bobbin. 0n the layer '10 of asbestos is spread a thin coat 11 ofcement or similar materiaLon whichis laid a thin metal plate 12, therebyforming a metallic covering or protection for the asbestos 10. Theentire bobbin with its'coil of wire isthus inclosed in asbestos orsimilar material, thereby insulating it both electrically and thermallyfrom. the shell 1, and at the same time the coil of wire 3 issimilarlyinsulated from the bobbin. Against the plate 12 rests an annular metalring 13. The spool with its asbestos covering fits tightly within theinterior of the shell or casing 1, and'the ring 13 fits tightly at theend of the spool, whereby the parts are held in position and a tight andcompact structure is formed, and at the same time the coil of 'wire isthoroughly protected from gases, wa-' ter, and heat in the cylinder towhich the plug may be attached. In my present 1nvention I have shown aring 13 for holding the parts in position, although it is obvious thatthe end of the casing 1 could be provided' with a flange in place of thering 13. A pin 14; is secured to the flange 5 of the bobbin, beingdesirably screw-threaded and screwed into said flange, The plate '11 isprovided with insulation 15, surrounding the pin '14.

. A ring or collar 16 is inserted in the end A of the casingl againstthe metal plate 12 and inside of the ring 13, the ring having a cut-'away portion to accommodate the pinld. The inner edge orface 17 of thering 116 is inclined or beveled. An armature 18 is arranged within thering 16 and adapted to vibrate toward-and away from the n'iagnet. A lug19 is formed on the inner face of the armature 18 to prevent it fromsticking to the plate 12, and a lug 20 is also provided on the outerface of said armature. The lug 20 strikes against theffbent end of thepin 14 and makes. contact therewith to close the circuit through thedevice.

.When the magnet is energized, the armature 18 is'attracted, so thatit-separates from the pin 14 and opens the circuit, creating a spark.This opening of the circuit deenergizes the magnet, releasing thearmature 18, whereupon the latter falls back, so as to make contact withthe pin 14 again. This closes the circuit again, causing the magnet tobe recnergized and the armature again attractcd and another sparkcreated. This action, causing a series of sparks, continues as long asthe circuit is closed.

- the nut 23 and. bushing 26, and the other end other is connected withthe engine-cylinder Thus a continual vibratory action of the arinsuredby its arrangement in connection with'the ring 16. The latter supportsthe ar mature at one side of its center of gravity, so that it tends tofall out and against the contact' 14, even though standing vertically.The ring 16, being an annular support, will support the armature nomatter what position the plug happens to be turned to.

'l.he end. B of the casing 1 is screw-threaded and provided with a metalplug or cap 21, which screws into said casing. in this cap 21 is anopening through which is inserted a threaded pin or spindle 22, on theinner end of which is a nut 23, the outer end being pro-' vidcd. withtwo nuts 24 and 25. There is also provided on the pin or spindle 22between the nuts 23 and. 25 and held firmly in place thereby aninsulating ring or bushing 26, preferably of lava or similar material,which ring 26 is of sullicient thickness to completely fill the spacebetween the pi1r22 and hole in the cap 2i, thereby holding the-pinfirmly in place in said cap. One end 27 of the wire forming the coil3"is connected with the pin 22, preferably by clamping between of saidcoil is connected with the metal bobbin.... One side of the battery isconnected with the pm 22 by the nuts 24 and 25 and the .or some otherpart of the engine. Thus the circuit is made from the pin '22 to thecoil 3, thence by the bobbin to the pin 14, and thence by the armature18 to the'shell 1 and engine-cylinder. to battery. When-the arma ture1.8 is attracted by the energization of the coil 3, said armature isseparated from the pin14, thereby opening the circuit and allowing: thearn'iature 18 to fall back against the pin 14" to thereby close thecircuit again.

mature is set up with the result of formation of sparks due to theself-induction at make and break.

The device is very simple and practical,

and in addition to the above-mentioned adi vantages of being thoroughlyprotected from 1 heat, gases, and water and being well insulatedelectrically it is very ellicient, requiring but a small percentage of.the usual amount of battery employed in devices of this kind,

for use in a horizontal oi-inclined position.

it will be understood that changes and modifications can be made in. thedevice herein deseribedwithout departing from the invention.

What l claim is----- 1. In a device of the class specified, thecombination of an electroinagnet, a loose armature, and an annularsupport which is arranged to support the armature at the inner side ofitslccnter of gravity.

In a device of the class specified, the combination of an clectromagnet,a loose armature thercfor, a contact for the armature on the outer sidethereof, and a supportfor the armature, said support being adapted andarranged to engage and support the inner edge of the armature.

3. in a device of the class specified, the

and, further-niore, it ia particularly adapted combination of ancleetroinagnet having a vertically-disposml armature, and a deviceinclosing said armature and provided with a supporting edge, thearmature having a groove adapted to receive said edge and located at oneside of the center of gravity.

4. In a device'of' the class specified, the combination of ahorizontallv-ilisposed electro'magnet having a vertically-disposedurinature, a ring inclosing the said armature and having an inclinedface forming a supporting edge for said armature, the latter beingprovided with an annular groove. toreceive said'edgc, and saidsupporting edge being located on the side of the center of grew ity ofsaid armature nearest said magnet. and a contact opposite the armature.

In witness whereof I hereunto subscribe my name this 2d day of Februarv,A. I). I 905,

. I, ,EREDUS A. 'rnu Rs'roN.

\Vitnes'ses.,'- I

ISABEL (3. l en,

, V. DO'MARUS.

